phunk's Whipple GT

[phunk]

EDIT 4/30/15: PLEASE NOTE this was an old/early tune file I was running. I want to be clear that the newer tunes have resolved this. I will keep the post otherwise available, but as of now this minor issue is no longer a concern.

I just dyno'd the car.

Something is happening on the top end... everything goes well and then at 6500rpm, I believe the throttle is starting to close. Boost and power go down, and I am down to 7-8psi. I tightened the belt up and there was zero change, which is why I believe its the throttle shutting. In 7-8 pulls it is totally identical, where I would expect any belt slip to be somewhat inconsistent as the belt temperature changes etc... and of course I would have expected at least an improvement after going full tight with the adjustable tensioner when it was in about 3/4 position before.

So every single pull goes drops power hard at 6500+.

Then I had what I think was some heat soak causing some other runs to go richer and down on power like 15-20hp or so.

Best run was 606 SAE and 619 STD, dynojet numbers. The horsepower line is straight as an arrow and looks like it would hit 640rwhp or so if only it didnt pretty much shut down at 6500. Runs were in 4th gear BTW.

Sooooo not really sure whats going on with it. I have to install the LTH's soon here... not sure if I will bother to redyno with this tune again or just go to a Lund tune.

Cool down / Glory pulls result in lower numbers. To run back to back the power goes up a few every time. I called it a day after 7 or 8 pulls, nothing much to see here.

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[Reds197]

The throttle closing is a common issue on the 15. Get with a custom tuner and get it fixed. If you are using SCT you can log throttle angle. Remember 85% is full throttle.
The stock Fuel pump can NOT be modded. Same as on 11-14. Trust me lots of people tried but it can't be done. This is a return less system with a regulator in the housing. You can add a boost a pump but that's it. The next step is a full return fuel system.

 

[phunk]

I wasnt exactly sure that I would mod the stock unit so much as just machine a new one

Wonder what is unhappy and telling the throttle to shut? I am pretty sure that every now and then on the street it stays open until redline, because there are some times where I floor it and I am convinced it made another 40-50hp than usual.

 

[Reds197]

Check out JPC Racing budget fuel system for some ideas.

There is something in the torque source telling it to shut if that is it. If you have SCT log throttle angle actual and see if its closing. It could also be pulling timing. So I would log both!

 

[phunk]

I gotta get my SCT ASAP. I tried logging with this Innovate iphone setup that works really well in my Z, but its refresh rate blows in the Mustang. I will order the SCT Monday and have it by Tuesday.

 

[Reds197]

Lund is coming out with an easy way to log. Check out Lund Racing Facebook. It would be money well spent IMO.

 

[phunk]

If you are talking about the nGauge they posted the other day, I want!!! I didnt check back to see if they mentioned a release date though. If its right around the corner, I can stand to wait... but if its going to be a while I would rather get my car sorted right away.

 

[Reds197]

Yes the nGauge. I think its coming in the next couple weeks.

 

[phunk]

Hmm... Wonder what that guy will cost.

I could just install my LTH for now and enjoy the car. Its not like its the worst thing ever to only have 600rwhp, I could tolerate it for a little bit LOL.. then just as they release their nGauge, install the fuel system and do the E85 tune.

I will also check in with Whipple and see if they have anything they want to try that might keep the throttle open to redline.

 

[phunk]

heres the graph of the best run, SAE version.

 

[Reds197]

Throttle is definitely closing. Get with Lund they can help you. I am pretty sure SCT is not capable of tuning this out. Contact them first before you buy an SCT.

 

[Reds197]

There is also 60-70hp left in the tune. It would be money better spent vs long tubes IMO.

 

[phunk]

Maybe I should even let the dust settle for maybe 2 weeks and then try hitting up both Whipple and Lund and see what they each say about it.

I already have the long tubes and I like the idea of them simply because its a way to unlock a little more power by just reducing pumping losses... its power without working the engine harder.

I have a goal of about 725rwhp on E85. Hoping to not have to go too much smaller on the pulley.

 

[Process]

Torque management setting, I'm not saying HPTuners is what will solve it, but I'm tuned with it, and have zero issues with the throttle.

 

[Reds197]

If you have put them on and then get a tune. It will be 800+ if you want. I would stop at 700ish.

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